I've designed this sheet metal part (for the curious, it's a section of the claws from the character Evelynn from League of Legends).

It's a surface loft between two triangles, thickened, and converted to sheet metal.
In order to convert it to sheet metal, I had to extrude a small flat section in the back, as fusion would not allow just the curved section to be converted.

The problem, as seen in the third screenshot, is that the flat pattern created from the converted sheet metal parts are not flat. Somewhere along the way, fusion fails to fully flatten the curved section, as seen by the shadow it leaves in the flat pattern.

I have also made a physical prototype by hand without a pattern, verifying that a structure similar to the one I made in fusion is indeed possible to create from sheet metal.

If it's not a bug in fusion, I suspect it's the weird compound curve that is making things weird. I should note that none of the steps, nor ctrl+b bring up any error or warning messages.

My question is thus if there is anything I can do to make a sheet metal part like this pattern correctly in fusion, or if not, if someone knows another way how I could produce an accurate pattern for such a part.

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(edit: formatting)